Secure Cooperative Control Of A Class Of Linear Multi-agent Systems For Cyber Attack

In this paper,the linear multi-agent system subject to attack is taken into consideration,combining random switching of the topology caused by the attack?deception attacks and so on,respectively,adopting graph theory?switching control methods?output feedback control methods?event-triggered control methods and sliding mode control theory to study its secure consensus control and secure cluster consensus control.The main work includes the following three aspects:1.A distributed observer-based switching control strategy is proposed for a class of linear multi-agent systems that communication topology are randomly attacked and part of the states are not available.The topology will switch randomly caused by the attack,adopting Markov process to simulate the randomness of the topology switching,and use the Riccati equation and Riccati inequality to calculate the feedback gain.Considering that part of the states cannot be obtained,this paper designs the distributed observer to reconstruct the state of the system.Based on this,an observer-based secure consensus control strategy is designed to handle the attack and achieve leader-following secure consensus control in the mean square sense.2.In order to solve the problem of secure consensus control for a class of linear multi-agent systems in which the cooperative error information subjected to deception attacks,an event-triggered control strategy based on observer which is used to estimate consensus error is proposed.Considering that the communication links within the agent are subject to deception attacks randomly,Bernoulli sequence is adopted to simulate the randomness of deception attacks.The consensus error observer in this part designed for the linear multi-agent system under deception attack can estimate the sum of relative errors between agents.Based on the estimated signal from the consensus error observer,a consensus control strategy with event-triggered mechanism is proposed,which reduced the update times of the controller and saved the communication resources,and implements secure consensus control in the mean square sense.It turned out that there is no Zeno behavior.3.In order to solve the problem of secure cluster consensus for general linear multi-agent systems whose output information is attacked under directed acyclic topology,a cluster consensus control strategy based on sliding mode observer is proposed.The concept of equivalence transformation is used to retransform the system state into a measurable part and an unmeasurable part,and a sliding mode observer is proposed to estimate the state of the system under attack.Further,a secure cluster consensus control based on sliding mode observer is designed.It is proved by analysis that the cluster consensus is independent of the coupling strength between agents under the condition that the directed acyclic topology interaction is satisfied,and the stability analysis and simulation are given to prove that the control strategy designed can make the system achieve secure cluster consensus control.In summary,this paper studies the secure cooperative control problem of the attacked linear multi-agent system,using the state observer to reconstruct the system state,the cooperative error observer estimates the sum of errors between agents,event-triggered mechanism to save communication resources and adaptive sliding mode observer to deal with the uncertainty of the system,and designs a distributed switching control strategy based on the state observer,an event-triggered secure control strategy based on the cooperative error observer,and a cluster consensus control strategy based on the adaptive sliding mode observer respectively,to achieve secure cooperative control.